Compositions of 4-biphenyl acetic acid and method of use

ABSTRACT

THE COMPOUND 4-BIPHENYLACETIC ACID, ITS USE AND METHOD OF PREPARATION IS DESCRIBED. IT IS USEFUL FOR THE LONG LASTING AMELIORATION OF PAIN IN WARM-BLOODED ANIMALS.

unites "sees Patent once 3,784,704 COMPOSITIONS F 4-B1PHENYL ACETIC ACID AND METHOD OF USE Elliott Cohen, Pearl River, Adolph Edward Sloboda, New City, and Arnold Curtis Osterberg and Ralph Grassing Child, Pearl River, N.Y., assignors to American Cyanamid Company, Stamford, Conn. No Drawing. Filed Oct. 13, 1972, Ser. No. 297,540 Int. Cl. A61k 27/00 US. Cl. 424-317 4 Claims ABSTRACT OF THE DISCLOSURE The compound 4-biphenylacetic acid, its use and method of preparation is described. It is useful for the long lasting amelioration of pain in warm-blooded animals.

PRIOR ART Substituted 4-biphenylacetic acids are described, for example, in Eire Pat. 56/65, Belgian Pat. 664,187 (11/ 19/65), South African Pat. 65/4206 (3/ 10/66), French (Pat. 2401M (4/13/64). These references describe a variety of uses for the substituted 4-biphenylacetic acids. Esters of biphenylacetic acid are described by F. Blicke et al. (I. Am. Chem. Soc. '65, 1725 (1943) as antispasmodics although the base compound is not indicated as having any activity. G. Cavallini et al. (II Farmaco Ed. Scient H, 167 (1956) describe a number of substituted biphenylacetic acids as having anti-cholesterolemic activity. Other references such as British Pat. 034,534 (1/ 14/ 71) and T. Y. Shen, Chim. Ther. 2 (3) 459 (1957) describe a number of substituted biphenylacetic acids as anti-inflammatory agents.

DESCRIPTION OF THE INVENTION formula:

and a pharmaceutically acceptable carrier.

The preparation of the active component of the present compositions is described in the chemical literature by F. Blicke et al. J. Am. Chem. Soc., 65, 1725 (1943).

The 4-biphenylacetic acid has been found useful as a long lasting drug for the amelioration of pain in Warmblooded animals in doses which range from about 0.5 to 250 mg./kg./day. The preferred range of dose is usually from 5 to 50 mg./kg./day. In terms of drug per dosage unit for internal administration, one or more at intervals of one or several times a day may vary from about 50 mg. to about 500 mg. of therapeutic component. The present compound'can also be used parenterally or topically and formulations for such use are described hereinafter. Among the warm-blooded animals may be, for example, mice, rats, guinea pigs, dogs and the like.

One method of determining the drug etfect on conditions which result in production of pain is measuring the effect of acute inflammation in said warm-blooded animal. The following experiment using Royal Hart, Wistar strain 3,784,704 Patented Jan. 8, 1974 rats ranging from to g. was carried out. The rats were fasted overnight prior to dosing but had free access to water. The drugs in aqueous suspension were administered by gavage in a volume of 1.7 mL/SO g. rat (corresponds to hydration volume used by Winter et al., Proc. Soc. Exp. Biol. & Med. 111 544-547, 1962). The phlogistic agent used was carrageenin prepared as a sterile 1% suspension in 0.9% sodium chloride for routine testing. A volume of 0.05 ml. was injected through a 26-gauge needle into the plantar tissue of the right hind paw. Measurements were made 5 hours after drug administration (4 hours after carrageenin challenge) unless otherwise indicated. Volumes of both the normal and carrageenin inflamed feet were determined. The difference between the two measurements was considered to be the increased edema due to the carrageenin administration. Results were expressed as a C/T efiicacy ratio (edema of control animals/edema of treated animals). The following Table I summarizes the results. A compound is considered active if the C/T ratio 1.4.

TAB LE I The effects of anti-inflammatory agents on carrageenin induced edema the rat paw (pooled data) 1 Difiers significantly from controls (p= 0.05 by t test).

Another method of determining pain alleviation of the compound of the present invention is its effect as an active analgesic when measured by the writhing syndrome test for analgesic activity as described by Hendershot, L. C. and Forsaith, J. Journal of Pharmacology and Experimental Therapeutics, vol. 125, pages 237-240 (1958) with modifications. This method is based upon the reduction of the number of writhes following the intraperitoneal injection of one mg./kg. of body weight of phenyl pquinone in male Swiss albino mice weighing 15-25 grams per mouse. The syndrome is characterized by intermittent contractions of the abdomen, twisting and turning of the trunk, and extension of the hind legs beginning 3 to 5 minutes after injection of the phenyl p-quinone. The test compound is administered orally to groups of two mice each 30 minutes before injection of the phenyl p-quinone.

The total number of writhes exhibited by each group of mice is recorded for a 3-minute period commencing 15 minutes after injection of the phenyl p-quinone. A compound is considered active if it reduces the total number of writhes in two test mice from a control value of approximately 30 per pair to a value of 10 or less.

The following Table II summarizes the relative activity of the component of the present invention along with the activity of well known analgesics in this test.

TABLE II Number of writhes Oral per 3 min. period dosage,

Compound ing/kg. Pair 1 Pair 2 Aspirin l 200 3 3 Phenylbutazonc 1 5 4-biphenylacetic acid 5 3 Controls 1 30 30 1 Data for controls, aspirin, and phenylbutazone are historical averages using many pairs of animals.

Another method of determining the drug effect on conditions which result in production of pain is measuring the eifect on ultraviolet induced erytherna in guinea pigs. Albina guinea pigs. (Lederie breeding colony) were depilitated on their flanks, the evening before testing, with a standard mixture of barium sulfide and gum acacia. On the morning of testing, groups of four guinea were dosed by gavage one hour prior to ultraviolet exposure (1 hour.). At 0-hour they were restrained in a plastic container which allows exposure of 3 circular spots. They were then exposed to ultraviolet irradiation from a *Hanovia Kromayer lamp model for 60 seconds. To test for topical activity, the guinea pigs were tested immediately after exposure to ultraviolet light by dissolving the said compound in ethyl alcohol and swabbing the U.V. exposed areas with the aid of a cotton tipped applicator stick. At {+1 and +4 hours, the degree of erytherna for each of the three sites was assessed according to the following scoring system: 0=no erytherna, 0.5 incomplete circle or faint erythema and l.0=complete circle of distinct erytherna. Thus, the maximum score for each animal was 3.0. The following Tables III, IV and V summarize the results of the present compound and other drugs known to have a beneficial effect in erytherna in warmblooded animals.

TABLE III The effect of anti-inflammatory agents on development of erythema in guinea pigs (pooled data) Score (avg) Dead Dose, G.P./ Deci- Treatment mg./kg. 1 hr. 4 hrs. total sion Control 2. 1 2. 8 4/384 Aspirin 250 0.1 1.2 7/88 A 125 0. 1 2. 0 1/16 A 62. 5 0. 8 2. 0 2/11 A. 31. 3 1. 2 2. 3 0/ 12 Phonylbutazonc 250 0 0.5 2/60 A 125 0.1 1.1 0/16 A 62.5 0.3 0.9 1/12 A 31. 3 0. 4 1. 7 1/12 A 15.6 0.4 2.3 0/8 A 4-biphenylaeetic acid 250 0.1 2.6 0/8 A 125 0. 1 2. 1 0/8 A 62.5 0.1 1.6 1/8 A 31.3 0.2 1.3 0/8 A. 15.6 0.1 1.9 0/8 A 7.8 0.4 2.4 (/8 A 3.9 0.1 2.3 0/8 A. 1. 95 1. 2 2. 7 0/ 8 1 Oral administration.

NOTE .-A =Active (discriminant function analysis).

TABLE IV The eflect of varying the time pretreatment with various anti-inflammatory drugs on development of UV induced erytherna of guinea pigs (observation 1 hour after UV exposure) Erythema score obtained at various times l 1 hr. data from Table III.

2 16 control guinea pigs and 8 111 each treated group.

* :control guinea pigs and 41m each treated group.

l Jtatistically significant activity (discriminant iunetion analysis).

TABLE V The effect of topically applied biphenylacetic acid on development of erythema in guinea pigs (pooled data) Conc. of

applied Estimated Score (avg.) Dead solution, dose, G.P./ Deci- Treatment mgJml. mg. 1 hr. 4 hr. total sion Cnntrnl 2. 4 3. 0 0/21 i-biphenylacetic acid. 10 1.70 .3 2.3 0/16 A N oTE.-A=Active (discriminant function analysis).

Tests to show the eflect of said drug on chronic conditions of inflammation which produce severe pain were carried out in rats with adjuvant induced arthritis. Groups of three Royal Hart Wistar strain rats, weighing 200110 g. each were injected intradermally in the right hind paw with Freunds adjuvant (dried human tubercle bacilli in a mineral oil vehicle) at a dose of 2 mg./kg. of body weight. Test compound was administered orally in a 1.5% starch vehicle at the indicated dosage in mg./kg. of body weight once daily on days through 13 post-challenge. Control rats were treated in a similar manner, but given starch vehicle instead of the test compound. 0n the 14th and 21st day post-challenge the diameter of the injected paw (primary lesion) is measured by micrometer caliper, the volumes of inflamed paws are estimated from these measurements, and the results are expressed as percent inhibition of swelling as compared to controls at the same time. The other inflamed sites, such as ears, paws and tail (secondary lesions) are observed and the rat graded as to degree of inflammation and swelling present. The grading is based on a scale of 0 to 24.0, where 0 represents a complete absence of induced arthritic modules and 24.0 represents the maximum degree of inflammation. The mean grade for each treated group is calculated and the effects of each compound were expressed as percent inhibition of the control grade. The following Table VI summarizes the results obtained with 4-biphenylacetic acid and known anti-inflammatory agents.

TABLE VI TABLE VII Ratio of treated/control pressure-pain threshold Phenyl- 4-biphenyl- Aspirin butazone acetic acid Hours after treatment Nora-Analgesic action (duration) in the inflamed (brewers yeast) i at paw. Analgesia is considered to be present when the T/C ratio 1.5. There were at least 8 rats tested for each time period.

The efiect of anti-inflammatory agents on adjuvant arthritis of rats (treatment day 0 to 13) Percent inhibi- Percent inhibition Oral Dead/ Mean weight tion of swelling of score (secondary dose, treated gain (gms) (primary lesion) lesion) mg./kg.l at 21 Treatment day days Day 14 Day 21 Day 14 Day 21 Day 14 Day 21 Normal rats 4/51 1 69 1 100 Adjuvant controls 21/234 36 39 0 0 0 0 Phenylbutazonm. 150 0/18 1 S0 44 l 52 1 31 75 2/18 1 57 54 1 72 1 23 1 24 11 37. 5 2/18 47 5O 1 67 19 12 l 14 Aspirin 400 4/18 48 57 1 76 1 68 1 52 1 48 200 1/18 31 27 1 51 1 86 14 1 18 100 7/18 42 49 1 40 1 21 1 19 7 4-bipheny1acetic acid 25 6/27 37 44 44 1 27 2 12. 5 2/6 53 37 i 35 8 1 35 0 6. 3 2/6 40 26 23 4 15 18 1 Significantly difierent from adiuvant controls (p= 0.05 by t test).

Experiments were conducted to determine analgesia by a modification of the method of Randall and Selitto (Arch. Int. Pharmacodyn. 111: 409419, 1957) in rats whose paws were made sensitive to pressure by the injection of a 20% aqueous suspension (0.1 ml.) of brewers yeast into the plantar surface of the left hind jaw. Constantly increasing force (16 grams/second) was applied to the swollen paw using an Analgesy Meter, Ugo Basile. The pressure was cut oif at 250 grams of force when there was no response (sudden struggle or vocalization). Control rats treated with the starch vehicle respond to a pressure or force of about 30 grams. Pressure-pain thresholds were always recorded two hours after brewers yeast. Analgesic agents were administered at various times before or after the yeast depending on the duration of action being studied. Ratios of treated (T) control (C) reaction thresholds were calculated as estimates of analgesic eflicacy (degree of analgesia attainable). The ratios of pressure to react were determined from /2 to 24 hours following the administration of 200 mg./ kg. orally of 4-biphenylacetic acid, aspirin or phenylbutazone. The results are summarized in Table VII.

reacting a hot sodium hydroxide solution with uric acid crystals overnight according to the method described by McCarty, O. J., Jr. and Faires, J. S.,Current Therapeutic Research 5, 284-290 (1963). The resultant monosodium urate crystals were washed and'dried and resuspended in physiological saline to a concentration of 30 mg./ml. and sterilized by autoclaving. Suspensions of sodium urate crystals prepared in this fashion can be stored indefinitely.

Beagles from the Lederle colony were used in all experiments. They were housed in individual cages and kept under uniform conditions ad libitum feeding (Ken-L Ration), temperature, humidity and artificial lighting.

The dogs were lightly restrained and taught to lie quietly in dog cradle on their backs. To produce the synovitis, the knee was shaved and a sterile 20 gauge needle inserted into the knee (stifle) joint. The needle was left in place and a syringe containing the 30 mg./ml. sodium urate crystal suspension was attached. A volume of 0.1 ml. (3 mg. of sodium urate crystals) was then injected. An interval of at least 14 days elapsed between each use of a dog. The knees were alternated: thus each dog was used twice a month but each knee only once a month.

7 8 The degree of inflammation produced by the sodium EXAMPLE 3 urate injection was evaluated according to the following Ingredients: Grams scoring system: 4-biphenylacetic acid 75.0

' Talc 75.0 :Iggggfi 5 Magnesium stearate 2.5 P The ingredients are mixed, screened and tableted to three-legged galt give 500 tablets of 150 mg. each of 4-biphenylacetic acid.

4-Three-legged gait EXAMPLE 4 Drugs were administered orally by capsule or injected directly into the knee joint. Dogs were observed at hourly 10 Preparanon of Parenteral Solution intervals for seven hours. In a solution of 700 ml. of propylene glycol and 200 The following Tables VIII and IXsummarize the results ml. of water for injection is dissolved 20.0 g. of 4-biobtained. phenylacetic acid with stirring. After dissolution is com- IABLE VIII The efiect of biphenylacetic acid given 1 hour prior to challenge on the production sodium urate induced synovitis in dogs (pooled data) Mean score indicating severity of synovitis at various times (hrs.) after challenge Dose Number Oral treatment (mg/kg.) dogs 1 hr. 2 hr. 3 hr. 4 hr. 5 hr. 6 hr. 7 hr.

Control 31 1. 2 3. 7 3. 8 3. 9 3. 9 3. 7 4-bi1gienylacetic acid- 50 4 0 0 l 0 0 0 0 1 0 0 25 8 0 .3 .7 1.1 .7 .5 .4 D0. 12.5 7 0 .4 .5 .5 .4 .4 .3 Do. 6.25 4 0 0 .3 0 0 0 0 Do 3.1 3 0 1.3 2.3 2.7 2.0 2.0 2.0

l Statistically significant suppression of synovitis (p= .05).

TABLE IX The eflect of local intrasynovial injections of biphenylacetic acid on production of sodium urate induced synovitis in dogs (pooled data) Mean score indicating severity of synovitis at various Total dose times (hrs.) after challenge injected into Number Intralesional treatment joint (mg.) dogs 1 hr. 2 hr. 3 hr, 4 hr. 6 hr. 6 hr. 7 hr.

Control 31 1. 2 3. 7 4. 0 3. 8 3. 9 3. 9 3. 7 4-biphenylacetic acid. 2 0 1 0 1 5 1. 0 i 1. 0 2. 0 1. 5 Do 5 8 0 .5 -2.3 2.0 1.8 1.8 2.1

1 Statistically significant suppression of synovitis (p= .05).

The pharmaceutical carriers of the present invention plete, a solution of 5 g. of Z-aminoethanol in ml. of may be, for example, either a solid or a liquid. Exemplary water for injection is then added to the formulation. The of solid carriers are lactose, magnesium stearate, terra pH of this solution is then adjusted to 5.5 with hydroalba, sucrose, talc, stearic acid, gelatin, agar, pectin or chloric acid and the volume is made up to 1000 ml. with acacia. Exemplary of liquid carriers are peanut oil, olive distilled water. The formulation is filtered through a 0.22 oil, sesame oil and water. Similarly, the carrier or diluent micron sterilizing filter, filled into 5.0 ml. ampoules each may include atime delay material such as glyceryl monocontaining 2.0 ml. (representing 40 mg. of drug) and stearate or glyceryl distearate alone or with a wax. sealed under nitrogen.

A wide variety of pharmaceutical forms can be employed. Thus, if a solid carrier is used, the preparation can EXAMPLE 5 be tableted, placed in a hard gelatin capsule or in the form of a troche or lozenge. The amount of solid carrier will Toplcal Preparatlon vary widely but preferably will be from about 25 mg. to about 1 gm. If a liquid carrier is used, the preparation may 4'blphenylacetlc acld be in the form of a soft gelatin capsule or a liquid sus- Ethanol cc pensiom Methyl salicylate cc 5.0 SPECIFIC EXAMPLES Squalane The following examples dCSCI'ibC in detail formulations The ingredients are mixed together and used on intact which can be used in administering compositions of 4-bikin, phenylacetic acid. Wh t i l i d i EXAMPLE 1 1. The method for producing long lasting amelioration l g f s Grams of pain in a warm blooded animal which comprises ad- 4-blphef lylacetlc ministering internally or topically to said animal an Magneslum Steafate amount eifective to produce a long lasting anti-pain effect Lactose of 4-biphenylacetic acid in association with a pharma- Screen above ingredients through a No. 40 mesh screen. ceutically acceptame carrier- Transfer to mixer and mix well. Place in 100 hard gelatin The method In accordance Wlth clalm 1, 1n the form capsules. Each capsule contains a dose of 100 mg. which of a capsulemay be taken several times a day. 3. The method in accordance with claim 1, in the form EXAMPLE 2 of a tablet.

4. The method in accordance with claim 1, in the form Ingredients: Grams of a topical preparation.

4-biphenylacetic acid 50.0 Peanut oil 112.5 References Cited Mix above ingredients to a thick slurry and fill into Blicke 6t Chem- 5, 1725-1728 (1943).

1,000 soft gelatin capsules. Each capsule contains a dose of 50 mg. of drug. STANLEY J. FRIEDMAN, Primary Examiner 

